Method and apparatus for finishing a glass sheet

ABSTRACT

An apparatus for finishing a glass sheet comprising a pair of fluid bearings having bearing surfaces in opposing relation, the bearing surfaces spaced apart to define a channel for receiving the glass sheet, each bearing surface having a plurality of pores through which jets are introduced into the channel, the pores positioned on the bearing surface such that the jets produce a uniform fluid pressure across the bearing surface.

BACKGROUND OF THE INVENTION

The invention relates generally to apparatus and methods for finishingglass. More particularly, the invention relates to an apparatus and amethod for finishing a glass sheet having one or more pristine surfaces.

Glass sheets having surfaces that are pristine and of fire-polishedquality are usually made by fusion processes. Such glass sheets areuseful in making devices such as flat panel displays. A typical fusionprocess is illustrated in FIG. 1. Molten glass 100 flows into a channel102 of a fusion pipe 104 and overflows from the channel 102 and down thesides of the fusion pipe 104 in a controlled manner to form a sheet-likeflow 106. Because the outer surfaces 107, 109 of the sheet-like flow 106do not come into contact with any solid materials, they are pristine.The sheet-like flow 106 passes through a controlled heated zone 108 togradually cool down and therein form a continuous glass sheet 114 havinga desired flatness and thickness with pristine surfaces.

As the continuous glass sheet 114 emerges from the draw 112, a piece ofglass sheet is cut therefrom. The piece of glass sheet is then subjectedto a finishing process, which typically includes precision cutting ofthe glass sheet into a desired size using mechanical scoring, followedby edge grinding and/or polishing to remove any sharp corners and edges.Glass cutting by mechanical scoring and traditional edge finishing bygrinding and polishing produce glass particles that can contaminate thequality surface of the glass sheet. Extensive washing and drying areneeded to wash off the glass particles. This extensive washing anddrying impact the finishing line and manufacturing costs. The glassparticles can also damage the quality surface of the glass sheet.

From the foregoing, there continues to be a desire for improvements infinishing a glass sheet that would minimize the finishing line andmanufacturing costs and maintain the quality surface of the glass sheetin a pristine condition.

SUMMARY OF THE INVENTION

In one aspect, the invention relates to an apparatus for finishing aglass sheet which comprises a pair of fluid bearings having bearingsurfaces in opposing relation. The bearing surfaces are spaced apart todefine a channel for receiving the glass sheet. Each bearing surface hasa plurality of pores through which jets are introduced into the channel.The pores are positioned on the bearing surface such that the jetsproduce a uniform fluid pressure across the bearing surface.

In another aspect, the invention relates to a method of finishing aglass sheet which comprises loading a glass sheet in a channel definedbetween a pair of fluid bearings having bearing surfaces, wherein eachbearing surface has a plurality of pores through which jets areintroduced into the channel and the pores are such that the jets producea uniform fluid pressure across the bearing surface, and finishing edgesof the glass sheet.

Other features and advantages of the invention will be apparent from thefollowing description and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a continuous glass sheet produced by a fusion process.

FIG. 2A is a side view of a fluid bearing system.

FIG. 2B is a detailed view of a single fluid bearing.

FIG. 3A shows pressure profile observed from non-interacting water jets.

FIG. 3B shows pressure profile observed from interacting water jets.

FIG. 4 is an elevated view of an apparatus for finishing a glass sheet.

FIGS. 5A and 5B show an elevated view of an edge processing device.

FIGS. 6A and 6B illustrate processing device and fluid bearingarrangements.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described in detail with reference to a fewpreferred embodiments, as illustrated in accompanying drawings. In thefollowing description, numerous specific details are set forth in orderto provide a thorough understanding of the invention. However, it willbe apparent to one skilled in the art that the invention may bepracticed without some or all of these specific details. In otherinstances, well-known features and/or process steps have not beendescribed in detail in order to not unnecessarily obscure the invention.The features and advantages of the invention may be better understoodwith reference to the drawings and discussions that follow.

FIG. 2A shows a fluid bearing system 200 that supports a glass sheet 202while the edges of the glass sheet 202 are processed, e.g., cut, ground,and/or polished. The fluid bearing system 200 supports the glass sheet202 without contacting the quality zone (i.e., central portion) of theglass sheet 202. The fluid used in the fluid bearing system 200 may beliquid or gas. Where the fluid used in the fluid bearing system 200 isliquid, the fluid bearing system 200 also keeps the glass sheet 202 wet,thereby avoiding particle buildup on the surfaces of the glass sheet 202due to electrostatic charges. The fluid bearing system 200 includes apair of fluid bearings 204 arranged in opposing relation. The fluidbearings 204 are spaced apart to define a channel 206 for receiving theglass sheet 202. A set of edge grippers 208 grip the edges of the glasssheet 202 and prevent the glass sheet 202 from slipping out of thechannel 206. Preferably, the edge grippers 208 do not touch the qualityzone of the glass sheet 202.

FIG. 2B is a more detailed view of a single fluid bearing 204. The fluidbearing 204 includes a stack of plenums 210. The combined height (H) andwidth (W) of the stack of plenums 210 may be similar to the height andwidth of the glass sheet (202 in FIG. 2A). The spacing (S) between theplenums 210 may be the same or may be different. In some cases, theremay be no spacing (S) between some or all of the plenums 210.Alternatively, the stack of plenums 210 may be replaced with a singleplenum. Each plenum 210 includes a flow plate 212 and a support plate216 coupled to the flow plate 212 by inlet devices 215. The supportplate 216 is mounted on a support frame 218. The support frame 218 maybe coupled to alignment or positional devices (not shown), which wouldthen allow the fluid bearing 208 to be adjustable either relative to anopposing fluid bearing or glass sheet. The support plates 216 may alsobe adjustably coupled to the support frame 218, for example, so as toallow the spacing between the plenums 210 to be adjustable. The edges ofthe flow plates 212 may be tapered or flared to facilitate insertion ofthe glass sheet 202 into the channel (206 in FIG. 2A).

Inlet devices 215 have inlets 214 through which fluid from a fluidsource (not shown) may be communicated in between the flow plate 212 andsupport plate 216. The flow plate 212 has openings or pores (213 in FIG.2C) through which fluid from the inlets 214 can flow into the channel(206 in FIG. 2A) to provide bearing support to the glass sheet (202 inFIG. 2A) in the channel. In one example, the pores 213 are perforationsin the flow plate 212. In another example, the flow plate 212 is made ofa porous material. The fluid communicated to the pores 213 may be aliquid or gas. Preferably, the fluid does not interact with the glasssheet (202 in FIG. 2A). Examples of suitable fluids include, but are notlimited to, water and air. Preferably, fluid jets emerge from the pores213 to produce a uniform fluid pressure across the bearing surface 211of the plenum 210. To produce the uniform fluid pressure, the fluid jetsshould interact across the bearing surface 211 of the plenum 210. Forinteracting fluid jets, diameter (d in FIG. 2C) of the pores 213 ispreferably greater than ½ the distance between adjacent pores (D in FIG.2C).

FIG. 3A shows a pressure profile observed from non-interacting waterjets across a plenum surface. The pressure profile shows thatnon-interacting fluid jets would produce localized pressure on thesurface of the glass sheet. When the glass sheet is placed on such anon-interacting plenum surface, a water film is created between theglass and the plenum. However, the fluid pressure in the plane of thefilm water is non-uniform. The fluid bearing is very sensitive to smallperturbations in the jets (such as those produced by hole size variationdue to machining tolerances). The fluid flow non-uniformities and smallmisalignments of opposing jets can set up glass vibration that is highlyundesirable during an edge finishing process. FIG. 3B shows a pressureprofile observed from interacting water jets. As illustrated, thepressure profile for interacting water jets does not exhibit thelocalized pressure observed for the non-interacting water jets.

In general, plenum design to achieve uniform fluid pressure across avertical bearing surface is much simpler when the flow plate 212 is madeof a porous material. Porous materials create resistance to verticalflow due to gravity, thereby allowing uniform fluid spread across theplenum surface and thickness. A flow plate 212 made of a porous materialexhibiting the properties described above is preferred, i.e., diameterof the pores on the bearing surface 211 is greater than ½ the distancebetween adjacent pores. The use of thick, e.g., greater thanapproximately ⅛ in. (3.175 mm), porous material simplifies plenum designbecause fluid can redistribute itself evenly across the bearing surface211. Examples of porous materials include, but are not limited to,ultra-high molecular weight (UHMW) high density polyethylene (HDPE),available from, for example, GenPore, Reading, Pa. Porous materialshaving an average pore size in a range from 5 μm to 150 μm, preferably10 μm to 100 μm, more preferably 50 μm to 80 μm has been found to beuseful. The pores in the porous material may or may not be evenlydistributed and may have a variable size. The porous material thicknesstypically ranges from 10 mm to 50 mm, preferably around 25 mm. The fluidpressure drop through the thickness of the flow plate is preferably nogreater 50%.

FIG. 3B shows average pressure produced by interacting water jets as afunction of size of the channel (206 in FIG. 2A). As shown, averagepressure of interacting water jets decreases as channel size increases.Average pressure of interacting water jets is also influenced by thespeed of the jets, which is influenced by the size of the poresproducing the jets and the rate at which water is supplied to the poresproducing the jets. In general, the channel size and speed of the jetscan be selected to achieve a desired average pressure on the surface ofthe glass sheet. Preferably, the pressure applied to the surface of theglass sheet by the jets provides enough stiffness to support the glasssheet in the channel such that the glass sheet does not make contactwith the bearing surfaces of the flow plates. In some cases, it may bedesirable to apply different amounts of pressure to different parts ofthe glass. This can be achieved by making the flow plate with differentporosity sections, and tailoring the porosity in each section to achievea desired pressure across the corresponding section of the glass or bychanging water flow in a given section.

FIG. 4 shows an apparatus 400 for finishing a glass sheet. One or moreof the apparatus 400, or alternate embodiments thereof, may be used toachieve an efficient and cost-effective finishing line. The apparatus400 includes a platform 404, which is preferably rigid and may beequipped with vibration dampening mechanisms. A fixture 406 is mountedon one end of the platform 404. The fixture 406 supports a firstalignment (or positional) device 408. A support frame 410 is mounted onanother end of the platform 404, opposite the fixture 406. The supportframe 410 includes support bars 412 to which a second alignment (orpositional) device 414 is attached. The first and second alignmentdevices 408, 414 are spaced apart and are in opposing relation. Thefluid bearing system 200 is disposed between the first and secondalignment devices 408, 414 and coupled thereto. The fluid bearing system200 supports the glass sheet 202 during a finishing process whilemaintaining the quality zone of the glass sheet 202 in a pristinecondition.

The first and second alignment devices 408, 414 may be operated toadjust the position of the fluid bearing system 200, or componentsthereof, as necessary, for example, relative to the platform 404 orglass sheet 202 or processing devices 500. The first and secondalignment devices 408, 414 may be translation stages capable oftranslating components of the fluid bearing system 200 in one or moredimensions. For example, the first and second alignment devices 408, 414may be x-y stages, which may be driven manually or automatically, forexample, using motors, such as DC or stepper motors or servomotors. Thex-y stages may be compound stages or may be made of individualtranslation stages. A stage or actuator providing translation in fewerthan two dimensions may also be used as the alignment devices 408, 414.For example, adjusting components of the fluid bearing system 200 alongthe y-axis only may suffice. The alignment devices 408, 414 may alsoincorporate tilt platforms to allow for angular adjustment of the fluidbearing system 200.

The support frame 410 supports third and fourth translation stages 418,420. A processing device 500 for finishing an edge of the glass sheet202 may be coupled to each of the third and fourth translation stages418, 420. Only the processing device 500 coupled to the thirdtranslation stage 418 is visible in the drawing. The third and fourthtranslation stages 418, 420 may extend the processing devices 500 to thefluid bearing system 200 in order to finish the edges of the glass sheet202 supported in the fluid bearing system 200. A retractable bottomconveyor 424 is mounted on the fixture 406. The bottom conveyor 424 maybe used to transport the glass sheet 202 into the fluid bearing system200. After the edge grippers (208 in FIGS. 2A and 2B) grip the edges ofthe glass sheet 202, the bottom conveyor 424 may be retracted from thefluid bearing system 200 to allow access to the bottom edge of the glasssheet 202.

The processing device 500 could be any suitable device that can be usedto finish an edge of the glass sheet 202, such as a grinding, scoring,or polishing device. Preferably, the processing device 500 preventscontaminants generated during processing of the edges of the glass sheet202 from reaching the quality zone of the glass sheet. A suitableprocessing device is disclosed in U.S. Patent Application PublicationNo. US 2005/0090189 (Brown et al.), the content of which is incorporatedherein. FIGS. 5A and 5B show an example of a processing device 500disposed above the fluid bearing system 200. The processing device 500includes a finishing device 502. In one example, the finishing device502 includes a finishing wheel 504, such as a scoring or grinding wheel,coupled to a spindle 506. The processing device 500 further includes ashroud 508 which encapsulates the finishing device 502. The shroud 508includes a slot 509 through which the finishing wheel 504 accesses theedge of the glass sheet 202. Contaminants generated during the edgefinishing, e.g., glass particles and agents that aid in finishing of theedge of the glass sheet, such as water and other lubricants or coolant,are contained in the shroud 508. The contaminants in the shroud 508 areevacuated through a vacuum line (510 in FIG. 5B). The processing device500 may also include an air knife or a water knife 512 attached to theshroud 508 to prevent contaminants not collected by the vacuum line 510from escaping.

When the edges of the glass sheet are cut using a processing device witha shroud, the quality zone of the glass sheet is protected from thecontaminants produced during the finishing process. The edges of theglass sheet can be finished with tools such as grinding and scoringwheel. Other finishing devices, such as slurry jet or nitrogen jet, mayalso be used in place of the grinding wheel. A shroud may be used withthe slurry or nitrogen jet devices to enclose the edges of the glasssheet. The shroud allows a chemical coolant or other lubricant to beused during the finishing process. The coolant is contained within theshroud, thereby avoiding staining of the quality zone of the glass. Useof a coolant, such as one that is silane-based, can increase theeffectiveness of the finishing tool, e.g., the grinding wheel, and canhelp heal cracks in the edges of the glass, resulting in stronger edges.The edge debris after finishing can be cleaned by water jet containedwithin the shroud.

Various arrangements of the processing devices 500 relative to the fluidbearing system 200 are possible. FIG. 6A shows a simplified view of anarrangement wherein processing devices 500 are provided at the top andbottom of the glass sheet 202 and are translated along the glass sheet202 to finish the top and bottom edges of the glass sheet 202. The fluidbearing system 200 is represented by phantom lines 600 to allow viewingof the glass sheet 202. The vertical edges of the glass sheet aregripped by edge grippers during the finishing process. To finish thevertical edges of the glass sheet 202, the glass sheet 202 can beremoved from the fluid bearing system 200 and transported to anotherprocess station having an identical arrangement. Prior to reaching thenext station, the glass sheet 202 may be rotated 90 degrees to allowprocessing of the remaining edges of the glass sheet 202 using anidentical arrangement. The rotation may be performed by a robot thatgrips the glass sheet 202 in the non-quality zone. Alternately, the edgegrippers 208 can be relocated to the top and bottom of the glass sheet202 and the processing devices 500 can be translated along the verticaledges of the glass sheet 202. This would allow all the edges of theglass sheet 202 to be finished at one station without rotating the glasssheet 202.

FIG. 6B shows another modification to the arrangement of FIG. 6A. Inthis example, the edge grippers 208 which grip the sides of the glasssheet 202 are coupled to an end-effector 602, which is in turn coupledto a translation or positional device 604, such as a linear slide. Inthis figure, the fluid bearing system 200 is also represented by phantomlines 600 to allow viewing of the glass sheet 202 and edge grippers 208.During a finishing process, the processing devices 500 are heldstationary at the top and bottom of the glass sheet 202 while the linearslide 604 is operated to move the glass sheet 202 relative to theprocessing devices 500 The glass sheet 202 is carried into the fluidbearing system 200 on a first bottom conveyor 606 and leaves the fluidbearing system 200 on a second bottom conveyor 608 for another stationhaving a similar or identical arrangement. The glass sheet 202 may berotated 90 degrees prior to reaching the next station. This example hasa higher throughput because the glass sheet 202 keeps moving.

The various arrangements described above could also be configured in ahorizontal orientation rather than the vertical orientation depicted inthe figures. In a horizontal arrangement, the fluid bearing would behorizontal. Any auxiliary equipment for handling the glass sheet, suchas bottom or overhead conveyor, edge grippers, robot suction cups,preferably touches the glass sheet in the non-quality area, typically5-10 mm from the edges of the glass sheet. Using the arrangements above,if the fluid in the fluid bearing is liquid, the glass sheet is kept wetinside the fluid bearing during edge finishing, which prevents particlebuildup on the glass sheet due to electrostatic charges. Keeping theglass sheet wet also prevents fluid stains on the glass sheet.

The following finishing process examples are presented for illustrationpurposes and are not to be construed as limiting the invention asotherwise described herein.

EXAMPLE 1

A continuous glass sheet is formed by a fusion process. As thecontinuous glass sheet emerges from the draw, a glass sheet of desiredsize is cut from the continuous glass sheet using a traveling anvilmethod (TAM). TAM involves scoring the continuous glass sheet using ascoring assembly that travels alongside the continuous glass sheet at aspeed that matches the speed of the continuous glass sheet. In astandard TAM cut, the scoring device is a mechanical scoring wheel. Justbefore scoring the continuous glass sheet, a robot hand applies suctioncups to the continuous glass sheet. The robot end-effectors coupled tothe suction cups travel with the moving sheet as well. Once the sheet isscored with TAM, the robot bends the sheet to separate it from thecontinuous glass sheet. The robot then hands the sheet over to anoverhead conveyor, which moves the sheet to another station. In thisexample, a set of rollers (or edge guides) grip the edges of thecontinuous glass sheet as the continuous glass sheet passes through thedraw, as is well-known in the art. In this case, the next station is astation where vertical bead removal (VBS) occurs, i.e., trimming of thevertical edges of the glass to remove beads. Typically, the beads areremoved before the glass sheet is cold; otherwise, too much stress mayset into the glass sheet. VBS is not needed if the edges of thecontinuous glass sheet do not pass through rollers (or edge guides) inthe draw.

EXAMPLE 2

A glass sheet as prepared in EXAMPLE 1 is processed on a finishing lineincluding one or more of the fluid bearing system of the invention. Thefinishing process includes cutting the glass sheet to size using athermal shock cutting process. Thermal shock cutting processes aredescribed in, for example, U.S. Pat. Nos. 6713720, 6204472, 6327875,6407360, 6420678, 6541730, and 6112967, the tutorial contents of whichare incorporated herein by reference. In general, the thermal shockcutting process involves heating the glass sheet along a narrow lineusing a heat source such as a laser or plasma torch. Heating of theglass sheet along the narrow line is immediately followed by rapidcooling of the glass sheet along the narrow line. The heating andcooling cycle creates a thermal shock in the glass in the vicinity ofthe narrow line, which results in a crack that propagates along thenarrow line. The glass sheet separates or can be easily separated fromthe glass sheet along the crack.

The glass sheet may be supported on an air bearing during the thermalshock cutting process. Air bearings can be simple, e.g., with holesblowing air to suspend the glass or air/vacuum combination such as NEWWAY® air bearings, available from New Way Air Bearings, Aston, Pa., orCore Flow air bearings. Alternatively, the fluid bearing systemdescribed above may be used with air as the fluid. After cutting theglass sheet to size, the edges of the glass sheet are finished whilesupporting the glass sheet in the fluid bearing system. A first set ofopposite edges of the glass sheet may be finished (cut andground/polished) simultaneously. Then, the remaining set of oppositeedges of the glass sheet may also be finished simultaneously with orwithout rotating the glass sheet. The glass sheet is then washed becauseTAM and VBS in EXAMPLE 1 are not clean. After washing the glass sheet,the glass sheet is dried using an air knife. The glass sheet is theninspected. After inspection, the glass sheet may be coated with aprotective coating. The glass sheet is then packed for shipping and/orstorage.

EXAMPLE 3

A glass sheet is finished as in EXAMPLE 2, except that the glass sheetis cut to size while supporting the glass sheet in a fluid bearingsystem and using processing devices with shroud.

EXAMPLE 4

A glass sheet is prepared as in EXAMPLE 1, except that TAM cut and VBSis by thermal shock process. The thermal shock process is clean and doesnot produce glass chips that can contaminate the quality zone of theglass sheet. The glass sheet is then finished as in EXAMPLE 2 or EXAMPLE3, except that final washing of glass sheet is not needed because TAMcut and VBS are clean.

The invention typically provides the following advantages. Extensivewashing and drying of the glass sheet typically associated with priorart finishing processes can be avoided where TAM cut and VBS are cleanas described in, for example, EXAMPLE 4 above. The finishing processesdescribed above can be easily integrated with fusion processes. Thefluid bearing system provides support to the glass sheet during the edgefinishing process without contacting the quality zone of the glasssheet. The fluid bearing system adds stiffness to the glass, enablingmore precise cut and preventing deformation during edge finishing of theglass sheet. The fluid bearing system can be used to control thetemperature of the glass sheet to maximize edge processing efficiency.The footprint of the processing line in the vertical orientation issignificantly reduced over a horizontal orientation. Contamination ofthe quality zone of the glass sheet while the glass sheet is in thefluid bearing system is avoided by shrouding the edges of the glasssheet during edge processing.

While the invention has been described with respect to a limited numberof embodiments, those skilled in the art, having benefit of thisdisclosure, will appreciate that other embodiments can be devised whichdo not depart from the scope of the invention as disclosed herein.Accordingly, the scope of the invention should be limited only by theattached claims.

1. An apparatus for finishing a glass sheet, comprising: a pair of fluidbearings having bearing surfaces in opposing relation, the bearingsurfaces spaced apart to define a channel for receiving the glass sheet,each bearing surface having a plurality of pores through which jets areintroduced into the channel, the pores positioned on the bearing surfacesuch that the jets produce a uniform fluid pressure across the bearingsurface.
 2. The apparatus of claim 1, wherein the pores are positionedsuch that the jets produced from the pores interact.
 3. The apparatus ofclaim 1, wherein a diameter of the pores is greater than one-half thedistance between adjacent pores.
 4. The apparatus of claim 1, whereineach fluid bearing comprises a flow plate, and a surface of the flowplate provides the bearing surface.
 5. The apparatus of claim 4, whereinthe pores in the bearing surface are provided by perforations in theflow plate.
 6. The apparatus of claim 4, wherein the flow plate is madeof a porous material.
 7. The apparatus of claim 6, wherein the porousmaterial has an average pore size in a range from 5 μm to 150 μm.
 8. Theapparatus of claim 6, wherein the porous material has an average poresize in a range from 10 μm to 100 μm.
 9. The apparatus of claim 6,wherein the porous material has an average pore size in a range from 50μm to 80 μm.
 10. The apparatus of claim 6, wherein a thickness of theflow plate is in a range from 10 mm to 50 mm.
 11. The apparatus of claim4, wherein each fluid bearing further comprises an inlet through whichfluid can be communicated to the flow plate.
 12. The apparatus of claim1, further comprising a processing device adjacent the fluid bearingsfor processing an edge of the glass sheet.
 13. The apparatus of claim12, wherein the processing device includes a finishing device forprocessing the edge of the glass sheet and a shroud for containingcontaminants generated during the processing.
 14. The apparatus of claim12, further comprising a mechanism coupled to the processing device formoving the processing device relative to the fluid bearings.
 15. Theapparatus of claim 12, further comprising a mechanism configured toengage the glass sheet and move the glass sheet relative to the fluidbearings.
 16. The apparatus of claim 15, wherein the mechanism comprisesa set of edge grippers and a linear slide coupled to the set of edgegrippers.
 17. The apparatus of claim 1, further comprising a conveyorfor transporting the glass sheet into or out of the channel.
 18. Theapparatus of claim 17, wherein the conveyor is retractable to allow aprocessing device access to an edge of the glass sheet.
 19. Theapparatus of claim 1, further comprising edge grippers extending intothe channel for gripping edges of the glass sheet.
 20. The apparatus ofclaim 1, wherein each fluid bearing comprises a plurality of the bearingsurfaces in a stack.
 21. A method of finishing a glass sheet,comprising: loading a glass sheet in a channel defined between a pair offluid bearings having bearing surfaces, wherein each bearing surface hasa plurality of pores through which jets are introduced into the channeland the pores are such that the jets produce a uniform fluid pressureacross the bearing surface; and finishing edges of the glass sheet. 22.The method of claim 21, wherein finishing edges of the glass sheetcomprises grinding and/or polishing opposite edges of the glass sheet.23. The method of claim 21, wherein finishing edges of the glass sheetcomprises advancing a finishing device to the edges of the glass sheetand moving the finishing device relative to the edges of the glasssheet.
 24. The method of claim 21, wherein finishing edges of the glasssheet comprises advancing a finishing device to the edges of the glasssheet and moving the edges of the glass sheet relative to the finishingdevice.
 25. The method of claim 21, wherein finishing edges of the glasssheet comprises finishing opposite edges of the glass sheetsimultaneously.
 26. The method of claim 21, further comprising cuttingthe glass sheet from a continuous glass sheet prior to loading the glasssheet into the channel.
 27. The method of claim 26, wherein thecontinuous glass sheet is produced by a fusion process and cutting theglass sheet is by a travel anvil method.
 28. The method of claim 27,wherein cutting the glass sheet is by a thermal shock process.
 29. Themethod of claim 26, further comprising removing beads from edges of theglass sheet prior to loading the glass sheet into the channel.
 30. Themethod of claim 27, wherein removing beads is by a thermal shockprocess.
 31. The method of claim 21, wherein finishing edges of theglass sheet comprises finishing a first set of edges of the glass sheetfollowed by finishing a second set of edges of the glass sheet.
 32. Themethod of claim 31, further comprising rotating the glass sheet prior tofinishing the second set of edges of the glass sheet.
 33. The method ofclaim 32, wherein the glass sheet is removed from the channel prior torotating the glass sheet and loaded into another channel defined by apair of fluid bearings prior to finishing the second set of edges of theglass sheet.
 34. The method of claim 21, further comprising washing theglass sheet.
 35. The method of claim 21, further comprising drying theglass sheet.
 36. The method of claim 21, further comprising coating theglass sheet with a protective coating.